胸腺五肽治疗大鼠扩张型心肌病的实验研究

The Treatment of Thymopentin in Rats with Dilated Cardiomyopathy

目的探讨胸腺五肽对扩张型心肌病(DCM)模型大鼠左心室重构和心功能的影响,及其对外周血中CD4、CD8、CD4/CD8、IFN-γ和IL-10的调节作用。方法将6周龄雄性Lewis大鼠45只随机分为正常对照组、胸腺五肽治疗组和盐水治疗组(每组15只)。胸腺五肽治疗组和盐水治疗组大鼠后肢足垫皮下注射猪心肌球蛋白,制成DCM模型,分别给予胸腺五肽和生理盐水28 d。行超声心动图、血流动力学及心肌组织病理学检查,ELISA法检测血清细胞因子,流式细胞术检测T淋巴细胞亚群。结果胸腺五肽组DCM大鼠LVIDd、LVISd显著减少,IVSd、LVPWd明显增厚,EF显著增加;左室短轴及左室截面直径显著减小;心脏质量/体质量比值及LVEDP显著降低,MBP显著升高;IFN-γ水平降低,IL-10水平升高;CD4及CD4/CD8显著降低,CD8显著升高。结论胸腺五肽可抑制心肌重塑,改善DCM大鼠的心功能状态;胸腺五肽可能通过提高IL-10水平,降低IFN-γ水平,调整CD4/CD8比值来调节DCM大鼠免疫失衡状态。

Objective To investigate the effect of thymopentin on the treatment of left ventricular remodeling and cardiac function in rats with dilated cardiomyopathy （DCM）, and on the regulation to CD4, CD8, CD4/CD8, IFN-γ and IL-10 in serum. Methods A total of 45 6- week-old male Lewis rats were divided into three groups, 15 of which served as normal contwls, 30 were subcutaneously injected with cardiac myosin by hind foot pad to induce DCM. After immunization, they were randomly divided into thymopentin treatment group and saline treat- ment group. The medical treatment continued for 28 d. Echocardiography, hemodynamics and myocardial histopathological examination were performed; serum cytokines were examined by ELISA assay; flow cytometry was applied to examine T-lymphocyte subsets. Results LVIDd, LVISd were significantly reduced in thymopentin treatment group of DCM rats; IVSd and LVPWd were obviously thickened, EF was significantly increased; left ventricular minor axis and left ventricular cross-section diameter was markedly reduced; the ratio of heart weight to body weight, and LVEDP were significantly reduced,and MBP was clearly increased; lower level of serum IFN-γ, and higher level of serum IL-10 were detected; the level of CD4 and the ratio of CD4 to CD8 were significantly reduced,the level of CD8 was evidently in- creased. Conclusion In the present study, thymopentin inhibited cardiac remodeling and improved heart function in rats with DCM. The re- sults also suggested that thymopentin probably regulated the immune imbalance of rots with DCM by increasing the level of IL-10,reducing the level of IFN-γ, and adjusting the ratio of CD4 to CD8.